Rains trigger modest sewage overflow

by: City of Lake Oswego, The city of Lake Oswego used Vactor trucks at the Cardinal Drive manhole to vacuum 91,000 gallons of wastewater on Monday.

The five inches of rain that fell in the Lake Oswego area earlier this week put the city's new overflow response plan to the test.

'The results were pretty astounding,' said Lake Oswego Public Affairs Manager Jane Heisler. 'I'm blown away at how successful we were.'

The city re-captured about 75 percent of the sewage overflow that was headed for the lake, said Heisler. Working early Monday morning through 11:30 p.m. Monday, the city employed three Vactor trucks, which essentially vacuum wastewater, at the Cardinal Drive manhole near Bryant. Each truck can hold about 2,000 gallons.

'We Vactored up 91,000 gallons,' said Heisler.

Still, more than 30,000 gallons made its way into Oswego Lake, which triggered the city's Code Red autodialing system, part of its overflow response plan. That automated system calls about 1,720 lakeside homes to alert them that sewage is going into the lake and they should not get in or near the water.

The plan is activated when the city gets more than an inch of rain in a 24-hour period or when flows into Tryon Creek Wastewater Treatment Plant exceed 13 million gallons a day.

The Cardinal Drive manhole is the city's 'canary in the coal mine,' said Heisler, meaning that when that manhole begins overflowing it signals that the pipes are backing up downstream and the city must begin using the Vactor trucks.

The city has two trucks and rented a third this week.

'We captured almost everything coming out of that manhole and kept it from getting into the lake,' said Elizabeth Papadopoulos, the city's director of maintenance services.

Once the trucks were filled, the city took them to a manhole on Oak Street, near McVey Avenue and emptied them.

In addition to the sewer system reaching capacity, the storm caused several landslides and rock-falls along Lake Oswego roads.

A rock-fall on Iron Mountain Road closed the bike path and a landslide on Green Bluff Drive blocked both lanes of traffic. Green Bluff was temporarily closed and re-opened Wednesday. Another small landslide was reported on Oak Terrace Road. A small landslide was reported on Highway 43, just north of Terwilliger Boulevard, in the southbound lane.

Also, a transformer blew at the corner of Boones Ferry Road and Country Club, temporarily knocking out the traffic lights on Sunday. And a power line was down on Lakeview Boulevard Monday morning, but it was not arcing.

The Lake Oswego Fire Department responded to downed power lines at Lakeview and at Bryant Road and Upper Drive.

Gert Zoutendijk, deputy fire marshal, said he knew of no injuries from the downed lines and no power outages.

In addition, Oswego Lake did not come close to the overflow stage, said a Lake Corp spokesman.

Although the threat of the sewage overflow was over by Tuesday morning, Papadopoulos said crews stayed on the scene until Wednesday, just in case.

People who were worried about flooding of their homes called the city's maintenance department for sandbags.

'We received a fair number of people calling for sandbags,' she said.

The number to call is 503-635-0280.

For the latest on the damage and problems caused by this week's storms in Northwest Oregon and Southwest Washington, log onto our Web site at www.lakeoswegoreview.com .